1. Department of Acute Care Surgery, University of Southern California, Los Angeles, California.
2. Department of Statistical Science, Southern Methodist University, Dallas, Texas.
3. Division of Burns/Trauma/Critical Care, Department of Surgery, Parkland Memorial Hospital, Dallas, Texas.
4. Division of Geriatrics and Palliative Care, Parkland Memorial Hospital, Dallas, Texas.
5. Division of Palliative Care, UT Southwestern Medical Center, Parkland Memorial Hospital, Dallas, Texas.